Alloy 825
2.4858 – N08825
Material search
Material description
The material 2.4858 is a titanium-stabilised, nickel-iron-chromium alloy with the additional alloying elements copper and molybdenum.
2.4858 (Alloy 825) has a number of positive material properties. The construction material is very resistant to acids and alkalis – even under oxidising and reducing conditions. 2.4858 has good corrosion resistance in various media such as sulphuric, nitric, phosphoric and organic acids as well as in ammonia, seawater and chloride alkalis.
Due to its nickel content, the alloy is also extremely resistant to chloride-induced stress corrosion cracking. The material also has good resistance to chloride-induced pitting and crevice corrosion. The good toughness at high temperatures up to approx. 550 °C rounds off the positive properties of the material.
AN OVERVIEW OF THE PROPERTIES OF 2.4858:
- Good resistance to (chloride-induced) stress corrosion cracking
- Good resistance to (chloride-induced) pitting and crevice corrosion
- Good toughness up to approx. 550 °C (even in continuous operation)
- Very good resistance to acids and alkalis (e.g. sulphuric, nitric and phosphoric acid, ammonia, seawater)
Applications
- Components for aircraft engines (e.g. hardware, nozzles, partitions)
- Moulds in pressing technology
Chemical composition in %
| ASTM B425/564 | VdTÜV Material sheet 432 | DIN 17744 | |
|---|---|---|---|
| Ni | 38,0 – 46,0 | 38,0 – 46,0 | 38,0 – 46,0 |
| Cr | 19,5 – 23,5 | 19,5 – 23,5 | 19,5 – 23,5 |
| Fe | 22,0 min. | Rest | Rest |
| Mn, max. | 1,0 | 1,00 | 1,00 |
| C, max. | 0,05 | 0,025 | 0,025 |
| Cu | 1,5 – 3,0 | 1,50 – 3,00 | 1,5 – 3,0 |
| Si, max. | 0,5 | 0,50 | 0,50 |
| S, max. | 0,03 | 0,010 | 0,015 |
| Al, max. | 0,2 | 0,20 | 0,20 |
| Ti | 0,6 – 1,2 | 0,60 – 1,20 | 0,60 – 1,20 |
| Mo | 2,5 – 3,5 | 2,50 – 3,50 | 2,5 – 3,5 |
| P, max. | 0,020 | 0,020 | |
| Co, max. | 1,00 |
Mechanical properties
| Soft-annealed | Bar | forging ASTM B425 | ASTM B564 | Bar | forging D ≤ 240 mm | Bar D ≤ 160 mm DIN 17752 |
|---|---|---|---|
| Rm (MPa) | ≥ 586 | 550 – 750 | ≥ 590 |
| Rp 0,2 (MPa) | ≥ 241 | ≥ 220 | ≥ 240 |
| Rp 1,0 (MPa) | ≥ 250 | ≥ 270 | |
| A (%) | ≥ 30 | ≥ 35 | ≥ 30 |
| Av (J) | l ≥ 120, q/t ≥ 80 | ||
| Hardness (HBW 2,5/62,5) | max. 210 |
The specified values are non-binding guide values.